PROJECT SUMMARY/ABSTRACT [The proposed research tests the hypothesis that atypical cerebral symmetries increase the risk for dyslexia through the expression of dyslexia-related genes that are known to regulate brain development.] While there were early promising findings linking planum temporale symmetry to dyslexia, study limitations due to small sample size, inconsistent measurement methods, and varied behavioral and genetic profiles of the subjects produced inconsistent results. [Here we examine planum temporale and other cerebral symmetries associated with dyslexia]. We address the limitations of previous studies by using a large dataset of existing genetic, neuroimaging, and behavioral data, as well as multi-site methods that we developed in the current funding period that make it possible to address dyslexia hypotheses with large multisite datasets. We have demonstrated the ability to deal with missing data, varied image acquisitions, and the behavioral heterogeneity of dyslexia samples that is influenced by sampling approaches. [Specific Aim 1 is to test the hypothesis that atypical cerebral asymmetries are observed for specific reading disability profiles, which are theoretically and empirically-grounded and map to different genetic risks. Specific Aim 2 is to examine the degree to which specific genetic risk variants for dyslexia influence the development of cerebral asymmetries. Specific Aim 3 is to develop the cloud-based infrastructure to provide investigators with secondary data for use in their studies and to replicate our findings (e.g., cerebral asymmetry measures related to dyslexia). The results will provide a consensus on the cerebral asymmetry hypothesis for dyslexia because of our large dataset and collaborative approach, provide behavioral neurogenetic explanations for dyslexia, and provide resources to the research community to advance our understanding of dyslexia and other developmental disorders.]